This invention relates to a recording and/or playback apparatus, and more particularly to a recording and/or playback apparatus called tape library which accommodates a plurality of cassette tapes and records or plays back data onto or from a selected one of the cassette tapes.
Where a large amount of data is handled, it is necessary to back up data of a server. Such backup is usually performed by recording data onto a compact disk. However, where a large recording capacity is required, a cassette tape, for example, an 8 mm tape or the like is used. Since much time is required for accessing to a cassette tape, a cassette tape is used to back up a large amount of data, while data which are used frequently are recorded onto and played back from a compact disk. A cassette tape has a storage capacity of approximately 50 to 100 GB.
A recording and/or playback apparatus called tape library for recording or playing back data onto or from tape cassettes requires an accommodation mechanism for accommodating cassette tapes, a recording and playback mechanism for recording or playing back the cassette tapes, and a feeding mechanism for feeding a cassette tape between the accommodation mechanism and the recording and playback mechanism.
A conventional tape library usually includes a cassette shelf which can accommodate a number of cassette tapes determined in advance, one or a plurality of drives for recording or playing back a cassette tape, and a feeding apparatus for feeding a cassette tape between the cassette shelf and the drive or drives.
However, since the conventional tape library can accommodate a fixed number of, for example, X, cassette tapes, if it is intended to accommodate more than X cassette tapes, then an apparatus of a special design must be ordered separately. Therefore, the intended apparatus cannot be acquired in short order and besides requires a high cost. Or else, if it becomes necessary to accommodate more than X cassette tapes after the tape library is purchased, then the tape library must be reconstructed. On the other hand, even where much less than X cassette tapes are required, the user is obliged to purchase a tape library which can accommodate X cassette tapes. In other words, the conventional tape library lacks in universality.